Public infrastructure and regional economic development: a simultaneous equations approach

A study of how public capital stock impacts regional economic development, which jointly models the effects of local public infrastructure on personal income and the effect of personal income on the allocation of local public outlays.Infrastructure (Economics) ; Regional economics ; Income

Correlation factor for diffusion in cubic crystals with solute-vacancy interactions of arbitrary range

A formalism using a double Laplace Fourier transform of the transport equation yields the return probabilities of the vacancy in the vicinity of the tracer atom in the presence of solute-vacancy interactions of arbitrary extension. Studying model cases, it is shown that taking into account the full range of the interaction may change noticeably the correlation factor. The latter depends tightly on the pattern of migration barriers which is chosen to describe the vacancy jumps around the tracer atom. A thorough ab initio evaluation of all barriers is rarely available in the literature. It is shown that approximations often used to overcome this lack of information can be misleading. The examination of dilute systems recently studied shows that the interactions within the first three neighbour shells dictate the final value with a good precision. The main improvement of the modelling comes from dropping the restrictive assumption which impose an equal value to the jump frequencies leading to a dissociation of the solute-vacancy pair.Comment: 45 pages; 8 figure

The role of landscape amenities in regional development: a survey of migration, regional economic and hedonic pricing studies

Quality of life factors continue to gain importance in residential location decisions as well as location decisions of firms. One such factor is an attractive local landscape. The aim of this paper is to provide a survey of the empirical literature on the role of landscape amenities in local economic change. Following common amenity definitions, we define landscape amenities as landscape features that are location-specific, latent non-market input goods that directly enter residents’ utility functions. Using this definition we identify thirty-nine relevant studies that use either migration or regional economic models or hedonic pricing techniques. One result from the analysis of migration and regional economic studies is that intra-country migrants were attracted by amenities about as frequently as by a low tax burden. Effects of amenities on employment and income are less well established. However, many of these studies used rather limited amenity variables. The results from hedonic studies show that a wide variety of local amenity attributes are partly capitalized in housing prices and that studies on a larger geographic scale are more likely to identify a significant a role of amenities. Newly available land cover datasets and spatial analysis tools have the potential to overcome important data limitations of many earlier studies. Future research may thus contribute to a better understanding of the role of landscape amenities in economic change and to a better coordination of regional and environmental policies.landscape amenities, migration, local development, hedonic models, environmental valuation, regional economic modeling, land use

Aromatic nitrations by mixed acid. Slow liquid-liquid reaction regime

Aromatic nitrations by mixed acid have been selected as a specific case of a heterogeneous liquid-liquid reaction. An extensive experimental programme has been followed using adiabatic and heat-flow calorimetry and pilot reactor experiments, supported by chemical analysis. A series of nitration experiments has been carried out to study the influences of different initial and operating conditions such as temperature, stirring speed and sulphuric acid concentration. In parallel, a mathematical model to predict the overall conversion rate has been developed. In this paper the mathematical modelling and the implementation and experimental validation for benzene, toluene and chlorobenzene mononitration in the kinetic control regime (slow liquid-liquid reaction) are presented and discussed

A versatile structure for GAS payloads

A strong, square cross-section, central column to which experimental and accessory compartments are attached is described. The attachment may be by direct bolting or through vibration and/or thermal isolators, as needed. Structural and thermal characteristics are evaluated

Co-Mn-Al mixed oxides promoted by K for direct NO decomposition: Effect of preparation parameters

Fundamental research on direct NO decomposition is still needed for the design of a sufficiently active, stable and selective catalyst. Co-based mixed oxides promoted by alkali metals are promising catalysts for direct NO decomposition, but which parameters play the key role in NO decomposition over mixed oxide catalysts? How do applied preparation conditions affect the obtained catalyst's properties? Co4MnAlOx mixed oxides promoted by potassium calcined at various conditions were tested for direct NO decomposition with the aim to determine their activity, stability and selectivity. The catalysts were prepared by co-precipitation of the corresponding nitrates and subsequently promoted by KNO3. The catalysts were characterized by atomic absorption spectrometry (AAS)/inductive coupled plasma (ICP), X-ray photoelectron spectrometry (XPS), XRD, N-2 physisorption, temperature programmed desorption of CO2 (TPD-CO2), temperature programmed reduction by hydrogen (TPR-H-2), species-resolved thermal alkali desorption (SR-TAD), work function measurement and STEM. The preparation procedure affects physico-chemical properties of the catalysts, especially those that are associated with the potassium promoter presence. The addition of K is essential for catalytic activity, as it substantially affects the catalyst reducibility and basicity-key properties of a deNO catalyst. However, SR-TAD revealed that potassium migration, redistribution and volatilization are strongly dependent on the catalyst calcination temperature-higher calcination temperature leads to potassium stabilization. It also caused the formation of new phases and thus affected the main properties-S-BET, crystallinity and residual potassium amount.Web of Science97art. no. 59